反应详情

Allyl mercaptan (2.12 g.) was added dropwise to a stirred suspension of ethyl 2-(2-formamidothiazol-4-yl)-2-(2-bromoethoxyimino)acetate (syn isomer, 5 g.) and potassium carbonate (3.95 g.) in N,N dimethylformamide (50 ml.) under ice cooling and stirred at the same temperature for 10 minutes and further at room temperature for 5 hours. After adding water (300 ml.) to the resultant solution, the mixture was extracted with ethyl acetate three times. The extracts were washed twice with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and concentrated in vacuo. The oily residue was subjected to column chromatography on silica gel and eluted with chloroform. The eluate was concentrated in vacuo to give ethyl 2-(2-allylthioethoxyimino)-2-(2-formamidothiazol-4-yl)acetate (syn isomer, 4.0 g.), mp. 62° to 64° C.

1. extractionthe mixture was extracted with ethyl acetate three times
2. washThe extracts were washed twice with a saturated aqueous solution of sodium chloride
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo
5. washeluted with chloroform
6. concentrationThe eluate was concentrated in vacuo